Combination lock



FIG. 1 is a perspective view showing a combination lock of my new design;

FIG. 2 is a front side view;

FIG. 3 is a rear side view;

FIG. 4 is a left side view;

FIG. 5 is a right side view;

FIG. 6 is a top view; and,

FIG. 7 is an under side view. 

The ornamental design for a combination lock, as shown. 